In the 12 weeks before the approval he had been earning $500 a week due to overtime, but just a few months earlier that amount was a mere $150 a week, News.com.au reports.

When the mother was made aware of the loan she had reportedly tried to call to get the loan cancelled and went into the bank with her son.

They were allegedly told that they could not cancel it on the spot but instead would have to make a complaint.

“On 29 September 2017, the income was verified automatically through our system, the contract was accepted online through NetBank and the loan was funded,” the CommBank complaints officer said.

The woman had reportedly tried to go into a branch to cancel a personal loan issued to her teenage son. Source: AAP

The woman's complaint was reportedly settled last month.

A Commonwealth Bank spokesperson told Yahoo7: "Commonwealth Bank lends according to individual risk profiles which take into account a number of factors including a borrowers’ ability to service that loan and their previous credit history.”

The bank said its processes are in line with industry standards and practices.

A customer who is trying to receive a loan can cancel their application prior to submitting an application, prior to accepting an offer and prior to accepting the contract.

Customers can also cancel an application over the phone before the money hits an account.

The mother told the publication that for the younger generation “hitting a button is very simple”, but acknowledged online loan applications were okay for people who "know what they're getting into."

“I just think [there should be] a step in the process where a human rings you beforehand to explain [things like] the total interest. A lot of people don’t understand, especially a teenager. They think they’re bulletproof.”